ipoe: encapsulate statistics counters

Group the IPOE starting, active, and delayed offer statistics in struct ipoe_stat_t and keep the storage private to ipoe.c instead of exposing writable stat_* globals. This keeps ownership inside the IPOE control code while preserving the existing CLI and ACCEL-PPP-MIB counter semantics.

Route counter updates through ipoe_stat_*() helpers. Session setup, activation, teardown, and delayed offer queue paths no longer open-code individual counter increments/decrements; the update policy now lives beside the IPOE-owned storage and uses relaxed atomic operations for the simple state counters.

Make the CLI show-stat path render from a local snapshot and convert the IPOE SNMP starting/active scalars from watched raw pointers to scalar handlers. SNMP now reads through ipoe_stat_starting() and ipoe_stat_active(), removing the old ipoe_get_stat() pointer escape hatch.

Signed-off-by: Denys Fedoryshchenko <denys.f@collabora.com>

2 files changed, 67 insertions, 27 deletions

diff --git a/accel-pppd/ctrl/ipoe/ipoe.c b/accel-pppd/ctrl/ipoe/ipoe.c
index e215c565..42d142fe 100644
--- a/accel-pppd/ctrl/ipoe/ipoe.c
+++ b/accel-pppd/ctrl/ipoe/ipoe.c
@@ -180,9 +180,7 @@ static int conf_check_mac_change;
 static int conf_soft_terminate;
 static int conf_calling_sid = SID_MAC;
 
-static unsigned int stat_starting;
-static unsigned int stat_active;
-static unsigned int stat_delayed_offer;
+static struct ipoe_stat_t ipoe_stat;
 
 static mempool_t ses_pool;
 static mempool_t disc_item_pool;
@@ -225,6 +223,39 @@ static struct ipoe_session *ipoe_session_create_up(struct ipoe_serv *serv, struc
 static void __terminate(struct ap_session *ses);
 static void ipoe_ipv6_disable(struct ipoe_serv *serv);
 
+void __export ipoe_stat_get(struct ipoe_stat_t *stat)
+{
+	stat->starting = __atomic_load_n(&ipoe_stat.starting, __ATOMIC_RELAXED);
+	stat->active = __atomic_load_n(&ipoe_stat.active, __ATOMIC_RELAXED);
+	stat->delayed_offer = __atomic_load_n(&ipoe_stat.delayed_offer, __ATOMIC_RELAXED);
+}
+
+unsigned int __export ipoe_stat_starting(void)
+{
+	return __atomic_load_n(&ipoe_stat.starting, __ATOMIC_RELAXED);
+}
+
+unsigned int __export ipoe_stat_active(void)
+{
+	return __atomic_load_n(&ipoe_stat.active, __ATOMIC_RELAXED);
+}
+
+static void ipoe_stat_inc(unsigned int *stat)
+{
+	__atomic_add_fetch(stat, 1, __ATOMIC_RELAXED);
+}
+
+static void ipoe_stat_dec(unsigned int *stat)
+{
+	__atomic_sub_fetch(stat, 1, __ATOMIC_RELAXED);
+}
+
+static void ipoe_stat_move(unsigned int *from, unsigned int *to)
+{
+	ipoe_stat_dec(from);
+	ipoe_stat_inc(to);
+}
+
 static void ipoe_ctx_switch(struct triton_context_t *ctx, void *arg)
 {
 	if (arg) {
@@ -741,7 +772,7 @@ static void ipoe_session_start(struct ipoe_session *ses)
 		}
 	}
 
-	__sync_add_and_fetch(&stat_starting, 1);
+	ipoe_stat_inc(&ipoe_stat.starting);
 
 	assert(!ses->ses.username);
 
@@ -1058,8 +1089,7 @@ static void __ipoe_session_activate(struct ipoe_session *ses)
 		}
 	}
 
-	__sync_sub_and_fetch(&stat_starting, 1);
-	__sync_add_and_fetch(&stat_active, 1);
+	ipoe_stat_move(&ipoe_stat.starting, &ipoe_stat.active);
 	ses->started = 1;
 
 	ap_session_activate(&ses->ses);
@@ -1184,9 +1214,9 @@ static void ipoe_session_started(struct ap_session *s)
 static void ipoe_session_free(struct ipoe_session *ses)
 {
 	if (ses->started)
-		__sync_sub_and_fetch(&stat_active, 1);
+		ipoe_stat_dec(&ipoe_stat.active);
 	else
-		__sync_sub_and_fetch(&stat_starting, 1);
+		ipoe_stat_dec(&ipoe_stat.starting);
 
 	if (ses->timer.tpd)
 		triton_timer_del(&ses->timer);
@@ -1632,7 +1662,7 @@ static void ipoe_serv_disc_timer(struct triton_timer_t *t)
 		list_del(&d->entry);
 		mempool_free(d);
 
-		__sync_sub_and_fetch(&stat_delayed_offer, 1);
+		ipoe_stat_dec(&ipoe_stat.delayed_offer);
 	}
 
 	while (!list_empty(&serv->arp_list)) {
@@ -1651,7 +1681,7 @@ static void ipoe_serv_disc_timer(struct triton_timer_t *t)
 		list_del(&d->entry);
 		mempool_free(d);
 
-		__sync_sub_and_fetch(&stat_delayed_offer, 1);
+		ipoe_stat_dec(&ipoe_stat.delayed_offer);
 	}
 
 	if (list_empty(&serv->disc_list) && list_empty(&serv->arp_list))
@@ -1672,7 +1702,7 @@ static void ipoe_serv_add_disc_arp(struct ipoe_serv *serv, struct _arphdr *arph,
 	if (!d)
 		return;
 
-	__sync_add_and_fetch(&stat_delayed_offer, 1);
+	ipoe_stat_inc(&ipoe_stat.delayed_offer);
 
 	memcpy(&d->arph, arph, sizeof(*arph));
 	clock_gettime(CLOCK_MONOTONIC, &d->ts);
@@ -1692,7 +1722,7 @@ static void ipoe_serv_add_disc(struct ipoe_serv *serv, struct dhcpv4_packet *pac
 	if (!d)
 		return;
 
-	__sync_add_and_fetch(&stat_delayed_offer, 1);
+	ipoe_stat_inc(&ipoe_stat.delayed_offer);
 
 	dhcpv4_packet_ref(pack);
 	d->pack = pack;
@@ -1721,7 +1751,7 @@ static int ipoe_serv_check_disc(struct ipoe_serv *serv, struct dhcpv4_packet *pa
 		dhcpv4_packet_free(d->pack);
 		mempool_free(d);
 
-		__sync_sub_and_fetch(&stat_delayed_offer, 1);
+		ipoe_stat_dec(&ipoe_stat.delayed_offer);
 
 		return 1;
 	}
@@ -1869,7 +1899,7 @@ static void __ipoe_recv_dhcpv4(struct dhcpv4_serv *dhcpv4, struct dhcpv4_packet
 			if (!ses)
 				goto out;
 
-			ses->weight = weight = serv->opt_weight >= 0 ? serv->sess_cnt * serv->opt_weight : (stat_active + 1) * conf_weight;
+			ses->weight = weight = serv->opt_weight >= 0 ? serv->sess_cnt * serv->opt_weight : (ipoe_stat_active() + 1) * conf_weight;
 		}	else {
 			if (ses->terminate) {
 				triton_context_call(ses->ctrl.ctx, (triton_event_func)ipoe_session_terminated, ses);
@@ -2327,7 +2357,7 @@ void ipoe_serv_recv_arp(struct ipoe_serv *serv, struct _arphdr *arph)
 				list_del(&d->entry);
 				mempool_free(d);
 
-				__sync_sub_and_fetch(&stat_delayed_offer, 1);
+				ipoe_stat_dec(&ipoe_stat.delayed_offer);
 
 				break;
 			}
@@ -2624,14 +2654,14 @@ static void ipoe_serv_release(struct ipoe_serv *serv)
 		list_del(&d->entry);
 		dhcpv4_packet_free(d->pack);
 		mempool_free(d);
-		__sync_sub_and_fetch(&stat_delayed_offer, 1);
+		ipoe_stat_dec(&ipoe_stat.delayed_offer);
 	}
 
 	while (!list_empty(&serv->arp_list)) {
 		struct arp_item *d = list_entry(serv->arp_list.next, typeof(*d), entry);
 		list_del(&d->entry);
 		mempool_free(d);
-		__sync_sub_and_fetch(&stat_delayed_offer, 1);
+		ipoe_stat_dec(&ipoe_stat.delayed_offer);
 	}
 
 	while (!list_empty(&serv->req_list)) {
@@ -2704,10 +2734,14 @@ static void l4_redirect_ctx_close(struct triton_context_t *ctx)
 
 static int show_stat_exec(const char *cmd, char * const *fields, int fields_cnt, void *client)
 {
+	struct ipoe_stat_t stat;
+
+	ipoe_stat_get(&stat);
+
 	cli_send(client, "ipoe:\r\n");
-	cli_sendv(client,"  starting: %u\r\n", stat_starting);
-	cli_sendv(client,"  active: %u\r\n", stat_active);
-	cli_sendv(client,"  delayed: %u\r\n", stat_delayed_offer);
+	cli_sendv(client,"  starting: %u\r\n", stat.starting);
+	cli_sendv(client,"  active: %u\r\n", stat.active);
+	cli_sendv(client,"  delayed: %u\r\n", stat.delayed_offer);
 
 	return CLI_CMD_OK;
 }
@@ -2725,12 +2759,6 @@ static void print_session_type(struct ap_session *s, char *buf)
 		*buf = 0;
 }
 
-void __export ipoe_get_stat(unsigned int **starting, unsigned int **active)
-{
-	*starting = &stat_starting;
-	*active = &stat_active;
-}
-
 static void __terminate(struct ap_session *ses)
 {
 	ap_session_terminate(ses, TERM_NAS_REQUEST, 1);
@@ -2768,9 +2796,10 @@ struct ipoe_serv *ipoe_find_serv(const char *ifname)
 static int get_offer_delay()
 {
 	struct delay *r, *prev = NULL;
+	unsigned int active = ipoe_stat_active();
 
 	list_for_each_entry(r, &conf_offer_delay, entry) {
-		if (!prev || stat_active >= r->conn_cnt) {
+		if (!prev || active >= r->conn_cnt) {
 			prev = r;
 			continue;
 		}
diff --git a/accel-pppd/ctrl/ipoe/ipoe.h b/accel-pppd/ctrl/ipoe/ipoe.h
index 38f521e1..37c26a63 100644
--- a/accel-pppd/ctrl/ipoe/ipoe.h
+++ b/accel-pppd/ctrl/ipoe/ipoe.h
@@ -130,6 +130,17 @@ struct ipoe_session_info {
 	uint32_t peer_addr;
 };
 
+struct ipoe_stat_t
+{
+	unsigned int starting;
+	unsigned int active;
+	unsigned int delayed_offer;
+};
+
+void ipoe_stat_get(struct ipoe_stat_t *stat);
+unsigned int ipoe_stat_starting(void);
+unsigned int ipoe_stat_active(void);
+
 int ipoe_ipv6_nd_start(struct ipoe_serv *serv);
 
 #ifdef USE_LUA